Mcroberts keeping me from being employed

I requested an arrangement letter from Mcroberts attorneys, they refuse to give it to me. I can get a job but because i was unemployed for a while and couldn't pay my bills i was placed on ITC. I now have the opportunity to work again but the company requested that i submit an arrangement letter. Hiw can McRoberts attorneys refuse to give me a letter, i have an arrangement with them. If i can get this job i will be able to make my full payment, if they dont how do expect me to make any future payments.